Anti-friction and sliding bearings



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March l5, 1955 F, F. C, RsCHLA 2,704,230

ANTI-FRICTION AND SLIDING BEARINGS Filed April 6, 1949 EVEN :kW/ry 0 d@Nq X gq a r. a,

[rn/entan- ATTOMEY United States Patent "O ANTI-FRICTIoN AND SLIDINGBEARINGS Fritz Franz Conrad Rschlau, Frankfurt am Main, Germany,assignor to Herbert Clemmens, Los Angeles, Calif.

Application April 6, 1949, seriai No. 85,814

14 claims. (ci. 30s-s) The present invention relates to improvements inand relating to the manufacture of anti-friction and sliding bearingspermitting the manufacture of bearings of this kind with comparativelylow expenditure of material and labor yet having high load capacity andlong like service. AThese. sliding bearings have an additional featurein that they can be manufactured, according to the invention, in a greatvariety of sizes in the manner known with anti-friction bearings asreadily applicable and exchangeable units.

With the known anti-friction bearings and in particular ball bearingswhich can support either only radial or radial and axial loads, theinterconnection of the bearing parts is accomplished by rolling bodiesthat is balls interpositioned between the faces of the inner and theouter race. To permit the filling in of the balls and provide a strikingconnection with the inner and the .down to the base of theV raceway, sothat when the saidrecesses are opposed the balls can be inserted singlyinto the enlarged intermediate space. These recesses, 1g-H however,`weaken the cross section of the two races and reducegconsiderably theload capacityof the bearing. :Theaccommodation ofthe necessarygball cagerequires 4an ample distance betwen the balls, as in` the describedmanner of assembly the ball cage necessarily` ,consists of two rings,which enclose the balls laterally.

There must alsobe intermediate spaces of suiiicient width between theballs in order to permit the joining of the rings by rivetsA or thelike. The limited number of balls due to the necessity of providing forthe insertion of the balls and to accommodate the ball cage leads to ahigher load on every single ball and to a diminutionof the load carryingcapacity of the races.

With regard to the assembly the'depth of the raceway can only be madevery small, as with deeper racways the radial gap for the insertion of asufficient number of balls will be too small. The small depth of the`raceways results in the diagonally opposed edges of the raceways of theinner and the outer ring having to .sup-

portan increased load under axial vstress of the bearing and the ballshave a tendency to jam` between the raceway edges, the distance betweenwhich is far greater than the ball` diameter, and press them asunder.

With other designs of ball bearings constituting a further development,it has been tried to eliminate this drawback, partly by dividing one ofthe two races radially in two halves, in which case however the twohalves of the race after the insertion of the balls must be joined lbyadditional parts, as shrink collars or the like. This is not only everyonerous but also weakens the cross secy tion of the race at the placesat which the parts'used to join the two race halves project into thematerial. The axial load is in this case imparted in proportion to therace joining parts the cross section Of'which will always be smallerthan'- that of the race.

Also'with the known readily applicable sliding bearing units withdimensions as usual with anti-friction bearing units, there areconsiderable difliculties to overcome if it is necessary to insert aclosed race with spherical or curved vface intothe outer race in whichthe oil film,

" have been proposed for that purpose.

2,704,230 Patented Mar. 15, 1955 which in conformity with the art isindispensable with sliding bearings to obtain a liquid friction, shouldnot be detrimentally impaired by transversely running assembly jointsboth in the outer and in the inner race. All proposals for the assemblyof races with spherical or curved faces made hitherto have eitherrecesses provided in the outer race, which have to be lled up againafter partial or complete insertion of the race, or divided racesconsisting of separate concentric parts in order to permit theapplication of the unit into the outer race. Even if it is possible withconsiderable difficulty to close partially or tightly the assembly gapsby fillers, it is not possible to completely eliminate the drawback ofthe weakened cross section at these points and the detrimental eifect onthe oil film of separating joints extending transversely through theraceway. Both the llers and the parts for the assembly of the compositeinner race must be suiciently secured against falling out and againstaxial and radial displacement, which necessitates either an intricateshape of the parts of the bearing or further additional ICC fasteningmeans.

To obtain a safe operation there have been provided besides the partsfor the inner and the outer race, additional parts in the shape oflateral rings or lateral discs mounted into the apertures of the outerrace. YThese lateral parts have the task of protecting the revolvingbearing parts and the raceways from the penetration of for- ,eign matterand to separate them partly from the oil 'sions provided for withanti-friction bearings, it being necessary to reduce still more thelength of the bearing `which is already very short to enable the spaceso provided, to be used for the accommodation of the lateral rings. AThus the axial length of the sliding way is further reduced whichhighlyendangers the reliability in service of the bearing, even when makinguse of all remedies that The design of sliding bearings depends in ahigh degree onthe attainment of a bearing which is substantially fr'eefrom wear and tear in order to obtain a liquid frictionl vThis liquidfriction is obtained, as is known, by a hydrodynamic effect in which therevolving part carried by the rotating journal of the bearing is liftedsemi-circularly from the reposing bi-centricity into the bearingco-center, so that the metallic surfaces of contact of the bearing losecontact. This hydrodynamic effeet can only be effective, if in additionto the surface finish, properties of the material and bearing play,other conditions'are present, that is a sufficiently elevated journalspeed and oil pressure, and a consistency of the lubricant adapted tothe prevailing service conditions'. It

is`obvious that it is not always easily possible to meet theserequirements in every respect, particularly in the case where slidingbearing is substituted for a ball bearing as the service conditions forthe ball bearing are quite different.

The method according to the invention obviates all these drawbacks ofthe known designs and relates to the manufacture of sliding andanti-friction bearings with an inner and an outer race and rolling orsliding'bodies between them.

According to the invention lateral rings are provided at`their sidesfacing each other with grooves forming' a part of the rolling or slidingways, whereupon the' outer annular part of the unit thus formed isseparated rfrom the inner annular part thereof in a coaxial cylindricalplane, preferably extending through the centers or axles of the rollingor sliding bodies. The same position of the grooves in the two lateralrings forming the rolling or sliding ways simultaneously permits thegrooving thereof, having the desired cross section of the rolling orsliding ways by means of the same tool, thus-securing a conforinity trueto size and shape. This is advantageousnot only from a manufacturingstandpoint but also economi cally in comparison with the knownanti-friction bear# ings, the non-uniform faces of which have to bemachined with different tools and a plurality of operations.`

` In the drawings are illustrated the `forms 4of `embodiment for `theassembly of an anti-friction bear-ing which is in this case a ballbearing and of a sliding bearing. Further features of the invention willappear from .the following detailed description.

In the drawings:

Fig. l is a cross section of one (left-hand) lateral ring .with steppedoutside cylindrical surface and one half Aof the ball race for theassembly of a ball bearing.

Fig. 2 is a cross section of the (righthand) opposite .lateral ring forthe assembly of 'a ball bearing with `stepped internal cylindricalsurface and one `half lof the ball race.

Fig. 3 is across section of a similar (left-hand) lateral ring as inFig. l however for the assembly of a sliding .bearing with one half ofthe sliding way.

g Fig. -4 is a cross section of a similar (right-hand) lateral ring asin Fig. Zhowever for the assembly of a slidping bearing with onehalf of-the sliding way.

Fig. 5 is a cross section of a cylindrical ball cage 'through an axialplane.

. Fig. `6 is `a side elevation of the sliding ring for the bearingpartially in section along the line l-I of Fig. 7 is a view of the outercurved surface of the sliding ring with grooves ending vin it.

Fig. 8 is a cross section of an assembled ball bearing unit.

Fig. 9 is a cross section of an assembled sliding bearing unit.

According to Fig. 1 the (left-hand) lateral ring a .is stepped down onits outside surface substantially lin the tmiddle of its axial length sofar that an annular area Iz. perpendicular to the axis, of suicient'size is formed. A groove c constituting a part of the ball race ismachined therein, `the axial cross section of which correspondsapproximately to the half of the ball cross section. The -lateral ringthus designed therefore consists of `an Aouter .flange portionincorporating the ball race groove c and and an adjacent tubularportion. At the greatest :depth `of the ball race the lateral ,ring isprovided with anarrow, ,preferably inwardly pointed slot a' machined .in`axial direction, the depth of which is limited in so far as theconnection of the outer and inner ring parts `must Vbe maintained.

Fig. 2 shows the inside surface of the other (righthand) lateral ring esubstantially in the radial center plane thus forming an annular area finside and perpendicular to the axis, the diameter of which .isfonlytvery slightly smaller than that of the annular area .b of 'the.lateral ring a. The annular area f is formed with a groove ci`constituting asimilar ball race'portion arranged las to position and:shape symmetrically to the annular area f of the lateral :ring a .and.presenting a similar `slot .d1. The `second .lateral ring thus designedtherefore 'consists of an `internal .ange portion rincorporating l.theball racefgroove ci and an adjacent tubular'nortion.

The .stepped surfaces ,Q of the outside surface 'of ithe lateral ring aand that of the `inside surface h .of1th'e lat- :eral ring .e .arepreferably made slightly cone-shaped Aso that ythey `taper with the(left-hand) lateral ring a tonvards'the largerlatera] annular area(.tlangeportion and increase in diameter with the (right hand) oppositelaterallring ve towards the larger lateral annular area :(ange portion),`thus .providing after the assembly of 'the two rings (Figs. 8 and 9)the drawing together of the two ,lateralrin'gs a, e. .Tn the drawing thecone-shaped 'surfaces are illustrated enlarged.

.If 1in the foregoing or in .the .following there'isth'e question of theright-hand or of the left-hand`lateralzring, this is only 'for reasonsof better distinction. 'Of course the two rings may be exchanged inpractice.

'The lateral rings according to Figs. 3 and 4 `serve kto 'form a slidingbearing and are `provided in vlieu ofjia'll races each with a slidingway half i or ii, the axial-cross 'sections of which correspondsapproximately Y.to the halt' cross sectionof the sliding ring zillustrated in Figs. i6, 7 and 19, taking intoconsideration the Aplay of.thebearing .Instead of the radial slots d. di. the sliding way halvesi, .i1 4arelcept in every case slightlydeeper than halfftlie axiallength of the sliding ring z so that the latter canf4 not run uplaterally of the sliding way under axial load.

Otherwise the lateral r'ings are ltep't perfectly equal 'for theassembly of each predetermined size of an anti-friction or slidingbearing, with the exception of the races c, ci or sliding ways i1. Thelateral machining of the race halves is advantageous since theirsymmetry permits the exact transposition of their cross sections bymeans of the same 'tool to the corresponding -'opposite ring.

The inner revolving parts of the examples illustrated, 'namely acagek'for the balls lor rollers (Fig. 15), and the balls or cylindricalior barrel-shaped rollers in `the case of an anti-friction bearing or asliding ring z (Figs. 6, 7 and 9) .in the case of a sliding bearing, maybe inserted without difficulty into the open race or sliding way halves.The ball cage k preferably consists of a cylindrical ring provided onits periphery, namely in the middle of its axial length at regularintervals, with holes l -which are somewhat larger in diameter than theballs which they take up with aplay.

Ot' course, as already mentioned, such a cylindrical annular cage may bedesigned `to take up .also other-rolling bodies such as cylindrical orbarrel-shaped rollers. In suchcases the holes .must .be .formed soas tocorrespond to .the .largest crosssection .in axial direction at the sametime taking certain .play into consideration. Consequently the `racelhalves'have to be proled accordingly.

The distance m between the holes of the cage k can be made very small sothat as great a number o'f rolling -bodies as possible .can beaccommodated in the cage. 4When assembling, the cage k for the rollingbodies is ,positively `guided with the ring sides n remaimng freezlaterally of the holes in the lateral slots d, d1 of the :lateral ringsa, e with sutlicient .radial and axial play of .the raceways. Thus'therollingbodies (notillustrated) are .kept -on the .greatest extension oftheir surface so that they cannot jam in the cage when revolving.

lWhen assembling the bearing, that is, when joining ,the .rings a, e,`it is :preferable to cool the lateral .rings a (Figs. 1 and 3) until ameasurable diminution of the -diameters of their outside surfaces glisobtained, while the opposite lateral rings .e (Figs. 2 and 4) may beheated 4.so far as it is possible without detrimental effect `to thematerial. In this wayithe different diameters of the very slightlycone-.shaped surfaces, which preferably slightly intersect each .otherwhen .they have .the same .temperature, are temporarily equalized so`that the lateral rings g1, e .can :easily be joined. The assembly ofthe lateral .Iingsa, e is facilitated if the slotsd, di are providedwith .-an outwardly extending bore through which the air may escape.

After joining `the two lateral `rings a, e to `form lirst one completelyclosed ring ,in which the inner parts, namely the rolling bodies withcagek or a ,sliding ring z are invisibly completely enclosed, the joined.ring Iis maintained under .pressure -until an equalization oftemi'perature occurs or :the movement of heat .from one lateral ring tothe other ceases, .in order to favour during this time the process:ofmutual drawing together of the tswgfings towards the'common centralplane b-j (Figs.

By. means of a slight radially .ground `notch o in the .plane lateralareas .of the rings a, e, immediately adjacent -the radial slots d, d1`provided Ainside vthe joined ring or in the :axial ,plane of symmetryofthe crosssection of Lthevsliding ways i, ii, the completely .closed.ring .is lsep- -arated into two rings .p and q,1both of which areformed o`f the joined radial fring parts of the .original `lateralrings. The .inner rings q and the outer `ring p thus obtained, `beinginconnectinglengagement with the builtinrolling bodies and thetcagek'orthe built-in sliding ring z -now constitute -a .self-contained,readily applicable anti-friction or sliding bearing unit. Insubstitution of the ground notch `o `it :is also lpossible to grind off.the -gigside `of the `lateral rings a, e in a plane `up to the slotsPreferably the ground notches or the facefgrinding is madeonly deepvenough for the separation of the outer and theinn'er ring. Thusthepenctration of `foreign matter into the interior of the bearing isavoided.

."Ehe ysliding .ring z has, `in the example illustrated, anapproximately oval cross section with an inner sliding `way Ar -and a`congruent outer sliding way s which are limited at both ends rbylateral annular .areas t yinto which preferably slots u expandinginternally, preferably on the center line of the cross sectional area,are machilled. The lateral attenings t isolate the internal ring z fromthe oil level so that the lubricant is not submitted to a centrifugalaction and no formation of oil foam occurs which would bedisadvantageous because it impedes the oil supply and rmay lead torunning dry.

The slots u are positioned so as to have a slight inclination, so thatat the place of their greatest depth they lie one upon each otheras-illustrated in Figs. 6 and 9. Thus the axial cross section of thering z will be Z- or. S- shaped, due to which the ring obtains anelasticity wlthin the conditions provided by `the slots u which remainsetfe'ctivewith a correspondingly chosen material.

On its inner and outer surface, i. e. preferably in its plane ofsymmetry, the ring z is provided with narrow eccentric grooves v. Thegrooves taken, enlargingy at their ends w in the curved sliding ways rand s. In their greatest depth the grooves v present a number ofadjacent holes x through which both the grooves v and the slots ucommunicate with each other. In the operation of the bearing the slots userve, in addition to the previously mentioned purpose of heatdissipation, the reception of the .lubricant entering through the notcho into slots u fed through the passages x to the grooves v fordistribution over the sliding ways by means of the enlarged groove endsw arranged in the direction of rotation. The grooves enlarging in adirection opposite the direction of rotation catch the lubricantlaterally or to maintain it in the middle of the sliding way. As thesliding ways are kept somewhat deeper than the corresponding half axiallength of the sliding ring body z, a small intermediate space y isformed between the lateral areas t of the ring z and the inner and outerrings p and q of the bearing at the place of the notch o which favoursthe lubrication, prevents the axial mutual pressure of the bearingrings, so that edge pressure is avoided, but permits also a slightinclination of the journal axis within the limits of the bearing playand gives to the minimum elastic sliding ring z the necessary lateralfreedom of motion.

The sliding ring z constitutes the steel support of a bearing metal withwhich it is jacketed with metallic touch. As the bearing metal,corresponding in composition is more or less susceptible to shocks anddilates more than the steel core with rising temperature, the mutualmetallic touch as well as the smoothness of the sliding surfaces isendangered by the said influences. The invention obviates thesedrawbacks due to the unequal dilatation of the materials assembled inone unit by keeping the volume of the material of the sliding ringsmall,

by means of cavities provided by the radial slots, so that f on the onehand a heat retaining effect is impeded and on the other the heatdissipation is favoured. Further the susceptibility of the bearing metalto shocks, edge pressure or jamming owing to a faulty assembly isavoided by the pressure and shock absorbing action of the internallyminimum elastic ring.

As may be seen from Figs. 8 and 9, the parts incorporated between therolling or sliding ways c, c1 or i, i1 (cage or sliding ring) are almostcompletely enclosed by the externally completely plane inner and outerrings p and q curved down laterally as far as to the extremely narrowradial notch o whereby, as already mentioned, the penetration of foreignmatter into the interior of the bearing is prevented and a detrimentalformation of oil foam is avoided.

With the design according to the invention a sliding bearing operated bya rotating journal transmits the rotation by friction of the slidingways i1 of the inner bearing ring q to the sliding way s of the slidingring z so that the latter can be carried along in the direction ofrotation. As soon as the inner bearing ring q takes up more heat owingto friction the bearing play of the said sliding ways sliding upon eachother is reduced due to the dilatation of the inner ring, whereby thesliding ring z is carried along by the inner bearing ring q so that nowboth rings are rotating and the sliding ring z is sliding with its outersliding way in the sliding way i, i1 of the outer bearing ring as longas the sliding ring z growing under the influence of heat reduces theouter bearing play and increases the inner play so that the ring z nowwill come to a standstill and the sliding way i, i1 of the internal ringq cooperates with the sliding way s of the ring z. In this way acontinuous change of the sliding ways sliding upon each other will takeplace, which will continue following another sequence. As an oppositerotation of the inner andthe outer bearing ring will scarcely occur,only oneset of sliding vways will cooperate. Owing to-thiS circumstance,the operating set of sliding ways disposes totally of the lubricant fedto the radial slots u in consequence of the hydrodynamic suction effectfavoured bythe concentric slots v, so that the working sliding ways aresuiciently provided with lubricant.

I claim: i

1. An annular intermediate structure adapted to `form an anti-frictionbearing upon the cutting of 'a circular groove in each end face thereofcomprising a first ring and a second ring, said first ring comprisingVan outer radial ange portion provided with a groove in an axial end facethereof and an inner axial tubular portion adjacent said face, and saidsecond ring comprising an inner radial ange portion having a centralaperture forv receiving said axial tubular portion of the Erst-namedlateral ring and being provided on an axial end face thereof with agroove in alignment with said rst-named groove to define an annularchannel and an outer axial Vtubular portion adjacent said last-namedface defining an 'axial aperture adapted to receivev said radial flangeportion of the first-named lateral ring, the axial dimension ofk each ofsaid rings being equal and the combined axial width of the tubularportion and the flange portion of each of said rings corresponding tothe axial width of the complete annular structure formed by theinterengagement of the two rings, and anti-friction means disposed insaid annular channel, whereby when a groove is cut in the end faces adepth to communicate with said annular channel a bearing is providedwhich has anouter race and an inner race defined by the radially innerand radially outer halves, respectively of said lirst ring and saidsecond ring.

2. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim 1, wherein said face of said first-namedlateral ring is substantially at the center of the axial length of saidring to provide an annular area perpendicular to the axis of saidfirst-named ring.

3. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim l, wherein said face of said second-namedring is substantially at the center of the axial length of said ring toprovide an ann ular area perpendicular to the axis of said second-namedring.

4. An annular intermediate structure adapted to form an anti-frictionbearing as dened in claim 1, wherein the cooperating surfaces of saidrst-named lateral ring and said second-named lateral ring are conicallyshaped' for complementary engagement.

5. An annular intermediate structure adapted to form an anti-frictionbearing as dened in claim l, wherein the radially outer surface of saidinner axial tubular portion of said first-named ring tapers inwardly inthe direction of said radial ange portion and the radially outer surfaceof said radial flange portion tapers outwardly in the direction of saidinner axial tubular portion and wherein the radially inner surface ofsaid outer axial tubular portion of said second-named lateral ringtapers outwardly in the direction of said inner radial ange portion andthe radially inner surface of said inner radial flange portion tapersinwardly in the direction of said outer axial tubular portion.

6. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim l, wherein the grooves for the reception ofthe anti-friction bodies are plrovided at their inner ends with axialinternally pointeds ots.

7. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim l, wherein the cooperating surfaces of thetwo rings have slightly dierent diameters when at the same temperature.

8. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim 1, wherein the radial flange portions ofsaid first ring and said second ring meet along a radial plane passingthrough the center of the antifriction means disposed in said annularchannel.

9. An annular intermediate structure adapted to form an anti-frictionbearing as defined in claim 1, wherein said anti-friction means comprisea plurality of balls and wherein said channel is formed with continuousaxial slots and said balls are mounted in an annular cage having itssides received and guided by said slots.

7 11110. Anannular intermediatestructure .adapted nto formnatanti-friction bearingas dened in claim 1,"wherein said anti-'friction`means lcomprise a sliding body :in vthe form of a .ring disposed iin.'saidfchannel.

:11. Anannular intermediate 'structure adapted Ato `form Jimanti-'friction bearing as defined in claim 410, wherein saidanti-friction ring has .a vsubstantially oval crosssection.

11,2. `Am-annular intermediate structure :adapted .'to form ananti-friction bearing .Jas defined in .claim `10, wherein saidAanti-friction ring is tformed with non-,intersectingslotsextendingntoltheinterior of the ring, said slots pro- .jecting intodifferent halves .of the ring and overlapping themselves at theirinnermost ends. l

13. `An annular `intermediatestructure adapted to fo an antifriction-bearing .as .defined fin .claim 12, wherein the 1anti-friction ring isprovided approximately `in the plane perpendicular .to the axis of ltheannular structure with at Lleastone =groove along its Aperipheralsurface and 'the bottom ofsaid groove is formed with aperturescommunicating with said slots.

14. Anannularinterm'ediate structure adapted :to `form an`anti-frictionbearing:as definedlin claim 10, wherein the 8 anti-ricon:ing is `provided With ,at least fone along its :peripheral lsurfacelying approximately in the plane perpendicular Lto the annularstructure.

References VCited inthe leaof this ,patent UNITED STATES PATENTS

